Hannah was injured outside the Athena, a Columbia nightclub and restaurant, and had surgery, Tigers coach Mike Anderson said in a release posted on the school's Web site yesterday. The senior is averaging a team-high 14.7 points and 5.1 assists per game.

"While our primary concern in this case is Stefhon's well-being, we will go through the process of gathering facts surrounding this incident and we will proceed appropriately," Anderson said.

The altercation took place late Saturday night after Missouri returned from a 66-62 victory at Colorado. Police Sgt. Krista Shouse-Jones said the 22-year-old Hannah was "assaulted by an unknown assailant with an unknown object" and taken to a hospital. No arrests had been made in the case.

Missouri's next game is Wednesday at home against Nebraska.

Hannah is the latest Tigers player to be involved in an off-court incident since Anderson was hired about two years ago. Kalen Grimes, the school's leading rebounder last season, was dismissed from the team after being arrested for hitting a man in the face with the butt end of a shotgun in St. Louis last July.

Two days before Grimes' arrest, forward DeMarre Carroll, Anderson's nephew, was shot in the ankle outside of a Columbia nightclub. Police said Carroll was a bystander in that incident.

After Carroll was wounded, Anderson announced a no-tolerance policy in an effort to keep his players out of trouble.